Does anyone have any advice on buying a lathe for turning powderhorn buttplugs and screwtips, but also in regards to using it as an aid in gun building? Anyone here thinking on that same level/plan?
Size needed will depend on what you mean by "as an aid in gun building".
For a small lathe capable of doing tumblers and such I would not go smaller than a 9". These can be had with spindle bores around 1" from Grizzly and probably Harbor Freight as well. Expect 1000-1200 bucks. This will handle anything in the way of ramrod tips and powder horn parts too of course. They come with all the chucks and such you are likely to need.
If you might make breech plugs or bore barrels for breeches, shorten etc then the size needs to increase to give a 1 1/4 or larger spindle bore.
This means a 12" or larger and a 4 jar chuck as well as a three and the cost may increase though pretty good used lathes may be found that are not too scary. Especially in the east or around larger cities.
So think about what you want to do carefully. Having a lathe opens many possibilities. But small table top lathes are very limited. Nor does a lathe have to be a modern design, an older step pulley speed change lathe in good condition can be a real prize in our context.
Used lathes often cut a taper to a greater or lesser extent close to the headstock where most work is done.
Used gap bed lathes are problematical if the gap has ever been removed. Sometimes they don't go back in properly.
Dan